It is known that the cyclic amide polymer resins, such as aromatic polyamide resins and heterocyclic polyamide resins, exhibit excellent thermal properties, for example, a high melting point, an excellent heat resistance and an excellent flame resistance. Also, it is known that the cyclic amide polymer resins are soluble in amide type polar solvents and the resultant solutions can be utilized for producing shaped articles, such as fibers, fibrids, tapes and films, by various solution shaping methods.
Especially, poly-m-phenyleneisophthalamide type polyamides are useful for producing shaped articles and can be industrially produced by either one of the following two methods A and B.